Terminate custom module scripts on exit #1032
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(Fixes #358.) Subprocesses created for custom module scripts were previously left running when the parent Waybar process exited. This patch sets the parent-death signal of child processes (PR_SET_PDEATHSIG on Linux, PROC_PDEATHSIG_CTL on FreeBSD) to SIGTERM. Caveats: * This uses Linux-specific or FreeBSD-specific calls. I don’t know if this project targets other systems? * There is a possibility that Waybar exits after calling `fork()`, but before calling `prctl` to set the parent-death signal. In this case, the child will not receive the SIGTERM signal and will continue to run. I did not handle this case as I consider it quite unlikely, since module scripts are usually launched only when Waybar starts. Please let me know if you think it needs to be handled. Testing: * With `htop` open, run Waybar v0.9.5 with a custom module that has an `exec` script. Terminate the Waybar process and notice that the script’s subprocess stays alive and is now a child of the init process. * Run Waybar with this patch and follow the same steps as above. Notice that this time the script’s subprocess terminates when the parent exits.
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Thanks @matteodelabre! |
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(Fixes #358.)
Subprocesses created for custom module scripts were previously left running when the parent Waybar process exited. This patch sets the parent-death signal of child processes (PR_SET_PDEATHSIG on Linux, PROC_PDEATHSIG_CTL on FreeBSD) to SIGTERM.
Caveats:
fork(), but before callingprctlto set the parent-death signal. In this case, the child will not receive the SIGTERM signal and will continue to run. I did not handle this case as I consider it quite unlikely, since module scripts are usually launched only when Waybar starts. Please let me know if you think it needs to be handled.Testing:
htopopen, run Waybar v0.9.5 with a custom module that has anexecscript. Terminate the Waybar process and notice that the script’s subprocess stays alive and is now a child of the init process.